In a system for storing personal information such as, for example, customer information, there exists a technology for suppressing an information leakage. For example, when the system utilizes data including personal information, the data may be ciphered by replacing a portion related to personal information with somewhat different data from original data.
Also, in a system for transferring data of one user to another user, there exists a technology for generating different data based on stored data, and further generating information to be disclosed using the generated data.
There is a case where a system performs a processing such as, for example, an optional selection or a group division for target data in order to utilize the data. For example, the system may perform a processing such as, for example, compressing and totaling of some records satisfying a predetermined condition from a table including many records, combining a plurality of records stored in different tables, or deleting of duplicated records.
However, when the contents (values) of a portion of record are ciphered by being replaced with other contents having no relationship with the original contents, the system may not identify the relationship among a plurality of records. For example, if the system is not able to determine whether or not the plurality of records stored in a table are for the same person, there occurs a problem in utilizing data. In other words, there is a problem in that the system may not be able to perform some processing such as data compression based on ciphered values, or combining the records using the ciphered values as a key.
International Publication Pamphlet No. WO2009/078182 is known as an example of related art.